Process of making acetyl-cellulose plastic compounds.



ished form with or .nnrrnn saaarns ieaarnivir WILLIAM G. LnvnsAY, or cALnwnLL, new JERSEY. asslenor. TO THE CELLULOID COMPANY, or new YORK, n. Y., a CORPORATION or new annsnv.

PROCESS OF MAKING ACETYL-CELLULOSE PLASTIC COMPOUNDS.

No Drawing.

To all whom it may co'nr-er'n,

Be it known that l, \VILIJAM G. LINDSAY, a citizen of the United States, residing at Caldwell, county of Essex, State of New Jersey, have invented certain new and useful Improvements in Processes of Making Acetyl Cellulose Plastic Compounds, of which the following is a specification.

'lhe various compositions to which the present invention relates are employed in the arts, generally as imitations of natural substances, sometimes in their original finwithout incorporated colors and other inert substances, and sometimes as films which are used for photo graphic and other purposes.

Although the final or useful form of the different compounds of acetyl cellulose is that of a solid material, the different pro cesses of conversion into thisfinal solid form involve, as is well understood, the employment of solutions or mixtures of varying consistency as to plasticity, stiffness, or fluidity, depending generally upon the proportion and kind of solvent used to the amount of the original base,acetyl cellulose.

.It has long been known that camphor mixed with nitrocellulose upon the addition of ethyl alcohol becomes a solvent of the nitrocellulose in the cold or room temperature. I have found, however, that when that process is applied to acetyl cellulose no solvent action takes place, and the object of my invention was to find substances which when added to acetyl cellulose, would exert a solvent action upon the cellulose and produce a plastic mass which could be worked in a manner analogous to nitrocellulose-camphor compounds.

I have discovered that acetyl cellulose of the variety which is soluble in acetone can be made into plastic solids by the use of either tetrachlorethyl acetanilid or trichlormethyl acetanilid, or a mixture of the two, I

in conjunction with methyl alcohol in substantiallye'qual proportions of the solids' and;,the alcohol; and that the solventwill convert the cellulose 'and render. the. compound capable of being worked as in the case of-the nitrocellulose-camphor plastic art.

As oneexample of practising my inven" Specification of Letters Patent.

tion, I take 100 parts of an acetyl cellulose of the variety which is soluble in acetone and grind it orv mix it with from 25 to 40 parts of either one of the above named solids, tetrachlorethyl acetanilid and trichlormethyl acetanilid, or with 9.5 to 40 parts ofa mixture of the two solids. I then incorporate the mixture with {P011140 to Patented Apr. 20, Milo.

Application filed November 2?, 1911. Serial No. 662,744.

parts of methyl alcohol by stirring, and allow the mass to soak or macerate at room temperature in a closed vessel until gelatinization of the mass has taken place. The compound can then be worked upon the rolls or in a heated press or mold, as is usual in the nitrocellulose-camphor art. The block or cake thus produced can be cut into sheets and dried in the usual way; or, if desired, the composition may be molded in a suitable heated mold into the final shape desired.

If it should be desired to use a smaller proportion of the solids, as may be'necessary in order to produce a material having a high degree of hardness or solidity, and if this decrease in the amount of solids used results in a mixture having apparently little or no solvent action in the cold, gelatinization' may be brought about by heating a' mixture containing as low as 10 parts of the solid ingredients of the solvent to 100 parts of the acetyl cellulose (acetone soluble variety) and 50 or more parts of methyl alcohol. As to temperature, the most suitable one is easily ascertained by a few tests and dependsupon the consistency desired.

, Placing the mixture in a suitable closed vesthe application of heat, and'still further promoted by the joint application of heat and pressure. the solid ingredient or ingredients of the solvent to 80 parts of methyl alcohol will produce a comparatively thin solution with the aid of heat and pressure. This may be useful in-eases where a filtration can be' done under the influence Ofheat and pressure. A I

Aproportion of 10 parts of solution thus prodnced will solidify when cold, but it is best to remove theexcess of methyl alcohol byevaporation down to, say, equal parts of solids and methyl alcohol before cooling. v i v It will be understood that slight'variations in the proportions of the ingredients of my newsolvents andtheir proportion to the acetyl cellulose would not be a departure from the spirit of my invention, and it will likewise be-understood by those skilledin the art that it is permissible to mix the acetyl cellulose and the other ingredients of my new solvents in any order desired, so long as solvent action is not permitted to take place so soon as to prevent incorporation of the cellulose with the ingredients of the solvent.

vInconstruing the claims, it will be understood that trichlormethyl acetanilid is an equivalent of tetrachlorethyl acetanilid in the process of this invention, although it is tetrachlorethyl acetanilid in the presence of a small proportion of methyl alcohol.

2. The process of making acetyl cellulose plastic masses which comprises incorporating an acetone-soluble acetyl cellulose with tetrachlorethyl acetanilid' in the presence of a small proportion of methyl alcohol, the proportion of the alcohol being about one to one and one-half times the acetanilid ingredient.

WILLIAM G. LINDSAY.

Witnesses:

- J. E. HINDoNHYDE,

MABEL DENTON. 

